[2] A resident of Nagasaki, Yamaguchi was in Hiroshima on business for his employer Mitsubishi Heavy Industries when the city was bombed at 8:15 AM, on 6 August 1945.

[4] As the war dragged on, he was so despondent over the state of the country that he considered honor killing his family with an overdose of sleeping pills in the event that Japan lost.

[4] On 6 August, he was preparing to leave the city with two colleagues, Akira Iwanaga and Kuniyoshi Sato, and was on his way to the train station when he realized he had forgotten his hanko (a type of identification stamp common in Japan) and returned to his workplace to get it.

[5][6] At 8:15 a.m., he was walking towards the docks when the American B-29 bomber Enola Gay dropped the Little Boy atomic bomb near the centre of the city, only 3 kilometres (1.9 mi) away.

[4][8] At 11:00 a.m. on 9 August 1945, Yamaguchi was describing the blast in Hiroshima to his supervisor, when the American bomber Bockscar dropped the Fat Man atomic bomb over the city.

[4] When the Japanese government officially recognized atomic bombing survivors as hibakusha in 1957, Yamaguchi's identification stated only that he had been present at Nagasaki.

In his eighties, he wrote a book about his experiences, Ikasareteiru inochi ("A Life Well-Lived"), as well as a book of poetry,[9] and was invited to take part in a 2006 documentary about 165 double A-bomb survivors (known as nijū hibakusha in Japan) called Twice Survived: The Doubly Atomic Bombed of Hiroshima and Nagasaki, which was screened at the United Nations.

[15] His wife also suffered radiation poisoning from black rain exposure after the Nagasaki explosion and died in 2008 at the age of eighty-eight of kidney and liver cancer.

[21] Both Stephen Fry, the host of QI, and celebrity guests drew laughter from the audience in a segment that included examples of black humor such as asking if the bomb had "landed on him and bounced off".

A BBC spokesperson told Kyodo News, "We instructed our crew to delete the file since we have already issued a statement that the content was not appropriate".

Toshiko Yamasaki, Yamaguchi's daughter, appeared on NHK's national evening news and said: "I cannot forgive the atomic bomb experience being laughed at in Britain, which has nuclear weapons of its own.

[24] The Japanese Embassy, London, wrote to the BBC protesting that the programme insulted the deceased victims of the atomic bomb.

It was reported that Piers Fletcher, a producer of the programme, responded to complaints with "we greatly regret it when we cause offence" and "it is apparent to me that I underestimated the potential sensitivity of this issue to Japanese viewers".